Static sealing element for acoustically decoupled add-on pieces

ABSTRACT

The invention relates to a housing sealing cover ( 1, 10, 15, 18 ) for detachable liquid-tight fixing to an internal combustion engine, comprising an add-on piece ( 24 ) which is firmly connected to the housing, extending through the cover when in a mounted position. Said cover consists of a metallic or polymer support element ( 2 ) made of a single layer and is provided with an opening ( 25 ) for the add-on piece ( 24 ), wherein a seal ( 23 ) is arranged in said opening. Said seal comprises a sealing lip ( 3, 11 ) extending axially on the edge ( 26 ) of the opening ( 25 ) and a sealing lip ( 5, 12, 16, 19 ) extending radially in relation to the seal of the add-on piece ( 24 ). The radially extending sealing lip ( 5, 12, 16, 19 ) is retained in the opening ( 25 ) in an angularly and radially displaceable manner with respect to the support element ( 2 ).

The invention describes a housing closing cover for a detachablefluid-tight fixture on a combustion engine.

The increasing number of electronic components in and around enginesrequires an ever increasing number of solutions for fluid-tightimplementations for add-on parts, such as sensors, plugs, cables, etc.This applies especially to add-on parts such as speed and positionsensors in the timing mechanism that will pass the information from theinterior engine to external analyzing units. For this purpose the add-onparts, such as the sensors, must be fed outwards through the housingclosing cover. A series of housing closing covers are known to ensurethe tightness of this implementation.

From the EP 0 528 104 B1 a housing closing cover with a built-in shaftspanning the cover, which consists of a tread drawn sheet-metal coverthat has predominantly a cup shaped profile. Its floor surface has twooffset radially arranged radial surfaces, where bolt through-holes arearranged on the first radial surface for connecting the housing to betightened. The second radial surface is cascaded and displaced againstit in order to work as a receiver of a statically acting side seal andas a dynamic lip-seal for the shaft.

Thus, the housing closing cover has two independently acting seals thatwill seal, firstly, the housing closing cover statically against theengine and, secondly, dynamically against the shaft. The stiffconnection between the static and dynamic seal using the sheet-metalcover will have a negative effect on the possible angular offset of theshaft. Another disadvantage is that the dynamic seal can only follow aradial movement of the shaft under certain conditions.

In order to follow an angular offset of add-on parts on the engines inGB 562,456 a shaft seal is revealed in which the flexible connectionbetween the static connection to the engine and the dynamic shaft sealare provided. The shaft seal consists of elastomer rings with a metalsupporting element and a coaxial corrugated plate-shaped path that isfurnished in the shaft area with a radial acting snap ring.

With the help of such seals it is possible to adjust an angular offsetof add-on parts, however the assembly of such a shaft seal can be quitework intensive since these must often be pressed in place.

The challenge of the invention is to develop an acoustically decoupled,fluid-tight housing closing cover that will guarantee a static seal forthe assembly face and the add-on part, and that is able to adjust anangular offset as well as a radial shift of the add-on part.

As per the invention, this challenge has been solved by the featuresdescribed in the patent claim 1. Further advantages of this inventionare documented in the sub-claim.

The idea of this invention solves this challenge in the sense that thehousing closing cover is equipped with a built-in add-on part spanningthe cover that is tightly connected to the housing and consists of asingle-layer metallic or polymer carrier element that has an opening forthe add-on part. The opening has a seal configured in that has an axialsealing lip spanning the opening edge and radially, to tighten theadd-on part. This sealing lip spanning radially will be held against thecarrier element moving angularly and radially in the opening. Thetapered formation of the connecting zone will make the connection of theadd-on part to the carrier element more flexible. As per the inventionthis tapering occurs between the axial and the radial sealing lips ofthe seal. For this purpose, the tapering of the seal must only bedemolded enough to allow the seal to be more easily formed in the fusionzone area then in the area of the axial and radial sealing lips. Thus,the housing closing cover is able to adjust the position tolerancesbetween the add-on part and the engine and also between the boltconnection of the sheet panel and the engine opening.

This shows another advantage: now the housing closing cover can be moreeasily assembled and disassembled with the flexibly executed fusionzone. Now, the stiff add-on parts will no longer be damaged, especiallyduring the disassembling.

According to the invention, the design of the housing cover has anotheradvantage in that the add-on parts are decoupled acoustically to agreater degree. As a result acoustically decoupled systems often possessa greater stiffness that can negatively influence the decoupling effect.On the other hand the tapering of the fusion zone offers the advantagethat there will not be a stiff connection between the axial and radialtightening, so that vibrations cannot be transferred. Furthermore,individual coordination of the partial areas of the axial sealing lip,fusion zone and radial sealing lip can take place.

There is the suggestion in another implementation of this invention ofthe housing closing cover that the fusion zone of the housing closingcover can be formed in a wavelike manner, so that it has the form of agaiter seal or several disk-spring formed plates, configured one afterthe other. Here it is also conceivable that the fusion zone can bemanufactured using another material than the seal material. This can bea polymer or a metallic material.

In another development of this invention it is also possible to fit thecarrier element at the opening area with a bevel. Regarding the way itis lined up, the bevel is configured away from the assembly surface andserves on one hand to stiffen the carrier element and, on the otherhand, as a lighter connection and formation of the axial sealing lip.

To enable greater sealing power throughout the entire lifetime of thehousing closing cover it is recommended, according to the invention,that a spring ring be configured on the radial exterior peripheralsurface of the radial sealing lip of the seal. For this purpose thespring ring will be configured in the area of the extension of theadd-on part so that there is another radial force affecting the radialsealing lip and thus the add-on part.

Another way of influencing the sealing power is to include a stiffrotating ring into the radial sealing lip of the seal. This ring can bemanufactured using a metallic or high-strength plastic. On one hand thisring can be molded into a radial sealing lip or lie on the radialexterior surface of the radial sealing lip, keeping the ring positivelyengaged.

The following describes other implementation examples, according to thisinvention, of a housing closing cover with axial and radial sealing lipareas and a connection element. Details are given in drawings and belowin the description.

FIG. 1 Shows, using an implementation example of this invention, thesection of housing closing cover with an axial and radial sealing lipand a tapered fusion zone.

FIG. 2 Shows, using an implementation example of this invention, thesection of a housing closing cover with an axial and radial sealing lipand a tapered fusion zone and a spring ring in the radial sealing area

FIG. 3 Shows, using an implementation example of this invention, thesection of a housing closing cover with an axial and radial sealing lipand a tapered fusion zone and a stiffening ring in the area of theradial sealing lip

FIG. 4 Shows, using an implementation example of this invention, thesection of a housing closing cover with an axial and radial sealing lipand a tapered fusion zone and a stiffening ring on the radial exteriorsurface of the radial sealing ring.

In FIG. 1 the section is shown using a housing closing cover 1 accordingto the invention, consisting of a carrier element 2, a seal 23, an axialsealing lip 3, a fusion zone 4, an add-on part 24 and a radial sealinglip 5, whereby the add-on part 23 is kept in the opening 25 of thecarrier element 2. For this purpose the carrier element 2 is furnishedwith a through-hole 6 for an attachment bolt 7 and angled 8 in the areaof the axial sealing lip 3 so that an edge 26 is formed.

The fusion zone 4 between axial 3 and radial 4 sealing lips is molded ina wavelike manner 9 in this example.

In FIG. 2 the section is shown using a housing closing cover 10 with anaxial 11 and radial 12 sealing lip, a tapered fusion zone 13 and aspring ring 14 in the area of the radial sealing lip 12.

Another implementation example of the invention is portrayed in FIG. 3.The housing closing cover 15 is equipped in the radial sealing lip 16with a stiff ring 17. The ring 17 counteracts the relaxation of theelastomer sealing materials and acts simultaneously as a stiffeningelement.

In FIG. 4 the section is shown using a housing closing cover 18 that isequipped with a stiff ring 20 in the area of the radial sealing lip 19.The ring is configured on the radial exterior surface 21 of the radialsealing lip 19 and is kept positively engaged 22.

1-8. (canceled)
 9. A housing closing cover comprising: a carrier numberhaving a bottom surface to be positioned against a mating component andan opening in said carrier member; a fluid seal mounted in said openingof said carrier element having an annular axial seal lip facing in theaxial direction of the opening adjacent on edge of said opening toprovide a static face seal between said housing and the matingcomponent, and including an annular radial sealing lip disposed radiallyinwardly of said axial sealing lip for sealing a member projectingthrough said opening, and wherein said radial sealing lip is supportedfor angular and radial movement relative to said carrier withoutsignificantly impairing the sealing lip about the member projectingthrough the opening.
 10. The housing cover of claim 9, wherein saidfluid seal includes a fusion zone connecting said radial sealing lip tosaid axial sealing lip and enabling said angular and radial movement ofsaid radial sealing lip through flexing of said fusion zone.
 11. Thehousing cover of claim 9 wherein said carrier member includes an axiallyangled region adjacent said opening.
 12. The housing cover of claim 10wherein said fusion zone comprises a tapered neck region of said fluidseal having a wave form.
 13. The housing cover of claim 9 including aflexible retainer spring mounted on said fluid seal opposite said radialsealing lip.
 14. The housing cover of claim 9 including a rigid ringmounted on said sealing lip opposite said sealing lip.
 15. The housingcover of claim 14 wherein said rigid ring is molded in place in saidfluid seal.
 16. The housing cover of claim 10 wherein said fusion zoneis fabricated of a radially and angularly flexible material that isdifferent than that of the axial and radial sealing lips.